"We have no time for this.’ said Sarpedon, irritated. Time was an enemy here, as were so many factors. He switched to the all-squads vox. 'Squads Hastis, Krydel, spread out and find me the Galactarium building, then report back and hold tight. Squad Graevus, hold this location with me. Post forward troopers to spot contacts. Move out.’

HOUSE JENASSIS WAS located on Kytellion Prime, a planetoid with a superdense core (and hence Earth-standard gravity). Other settlements, undomed and exposed to the planetoid's cruel weather, dotted the barren landscape, mostly isolated trading settlements that had been founded by retainers released from House service. One of them, however, was a massively built compound with walls of sheer ferrocrete and watchtowers on every corner. This was the Kytel-lion Prime Adeptus Arbites precinct, where several squads of Arbites judges and suppression units were responsible for the protection of House Jenassis. Their presence next to the habitat was one of the many ways in which the Navigator House was repaid for its diligent service to the Emperor's fleets.

There were several events that would cause the Arbites to be mobilised. The breaching of the dome over House Jenassis was one of them, signifying as it did a potential meteorite strike or other disaster, or even an almost unthinkable direct assault on the House. Within minutes of the alarm going up, a column of riot control vehicles and APCs, loaded with heavily armed Arbites officers and judge commanders, was snaking rapidly along the short road towards the entrance to the dome ready to defend the estate of the Navigator House they had sworn to protect.

The precinct astropath, as per the protocols that had been in place since House Jenassis had come to Kytellion Prime, transmitted the distress call across the ether, alerting the highest authorities that the ancient and holy House Jenassis was violated.

A few scant minutes afterwards, it was answered.

SQUAD HASTIS HAD come across a few retainers with hunting rifles, and scattered them with a volley of bolter fire before moving into the palace itself. Without engaging the palace's automated servitor defences, the squad ascertained that the palace contained plenty of marbled galleries and lavish quarters, but no Galactarium.

Squad Krydel, heading the other way, had located the low building of marble with deep crimson lacquered panels and battlements plated with gold. It was located in a shallow depression in the landscaped gardens, surrounded by a ring of trees and with a marble-paved road winding to its collon-naded entrance.

The Soul Drinkers' enhanced senses had picked out handfuls of retainers from families bound into service by House Jenassis, straggling from their picturesque village on the other side of the grounds. They would be little more than a nuisance if any of them proved brave enough to attack, but they were not the ones Sarpedon was worried about.

'Ready to secure the structure.’ said Sergeant Krydel. His squad was crouched by the columns at the front of the building. Techmarine Solun was beside the sergeant.

'No time,' replied Sarpedon. 'We'll go in together.'

Sarpedon, Squad Graevus and the captive patriarch moved rapidly through the trees and up to the threshold of the temple-like building.

'Squad Hastis.’ voxed Sarpedon to the squad by the palace, 'advance to this position and maintain a perimeter.'

An acknowledgement rune flashed on Sarpe-don's retina. Hastis was a good, solid soldier, and Sarpedon feared the assaulting squads would need backing up soon.

With a gesture, Sarpedon sent the three squads into the building. It was dark and cool inside, and with the breach in the dome there was a new chill in the air. The walls were of huge blocks of multicoloured marble bordered with plated gold and shiny lacquered panels. Banners representing the branches of the Jenassis family hung from the ceiling, which got higher as the floor sloped downward. Most of the building was beneath the level of the surrounding landscape.

Sarpedon skittered on his altered legs close to Sergeant Krydel. Krydel was a tactical squad sergeant whose squad had distinguished itself when the Daemon Prince Abraxes had manifested on the Brokenback, and he had a reputation for utter unflappability. From the front Sarpedon could see the huge marble architecture opening up into a central gallery, exposed to the darkening sky and surrounded by elegant columns of jade. The open space was several hundred metres across, and in the centre was a raised circular structure of white stone. 'Solun?' voxed Sarpedon.

'The auspex reads plenty of activity,' replied the Techmarine. 'There's a lot of electronics beneath us. This place must have its own power source.'

Sarpedon led the Soul Drinkers across the stone, leaving a handful of Marines as a rearguard. Graevus hauled Phrantis Jenassis to the front alongside Solun.

'Open it.’ demanded the Techmarine.

'What do you want with it? What are you?' gasped the patriarch.

'Permission to do this the old-fashioned way?' said Graevus, unclipping a handful of anti-armour krak grenades from his belt.

'Granted.’ replied Sarpedon. Phrantis was hauled away as Graevus planted the grenades at seams between the blocks of the circular structure, then fell back.

The grenades went off with a sound like a string of gunshots, kicking a haze of marble splinters into the air. Phrantis whimpered as the stone shell of the Galactarium, wonder of the Imperium, fell away The Galactarium was an extremely complex construction of strange dull grey metal and glistening black psychoplastics, nests of concentric circles and spinning globes on delicate armatures. Slowly it unfolded like the legs of a spider, rings spinning, sections rotating, like a huge armillary sphere that blossomed to fill almost the whole courtyard. Beneath the gathering clouds the rings and armatures spun faster and faster until points of light began to shimmer in the air as if conjured. Strange shadows played around the assembled Space Marines as stars and constellations bloomed into existence above them.

'Hastis, secure this structure.’ voxed Sarpedon. 'Solun, get to work.'

The Techmarine ran beneath the spinning mechanisms towards the centre of the Galactarium. Already the map was solidifying in the air - a star map, the largest and most comprehensive ever constructed. The Imperium was too vast to ever be properly mapped, and no one had ever managed to even catalogue its inhabited worlds. But attempts had been made, and the Galactarium was the closest thing to success the Imperium had. There were few places not represented on the immense stellar map now spherically projected around the Galactarium.

The Galactarium was the pride of House Jenassis; it was spoken of with reverence amongst fellow Navigators and the Adeptus Mechanicus Explorator commands alike. It was a dangerous target because taking it left the Soul Drinkers momentarily visible and vulnerable, but it was the Chapter's only hope.

'Commander?' came a vox. It was Sergeant Hastis, leading his squad back across the grounds from the palace. 'We've got contacts. Arbites, coming in from the dome entrance. I count seven vehicles heading for the palace and five moving towards your position.'

'Understood. Do not engage, get back here and help maintain our perimeter.' 'Acknowledged. Hastis out.'

Sarpedon did not want to kill anyone here. There was no need. But if he had to, he would, and he knew his battle-brothers would do the same.

Solun drew threadlike cables from the interfaces in his armour and plugged them into the base of the Galactarium. The huge map display was flickering and a new image was ghosting over the starscape. It showed a low building set into frozen tundra, obscured by gun smoke and ringed by ditches and barricades. It moved jerkily as the recorder moved closer, explosions flashing, armoured alien figures returning fire and spasming as silent bullets hit them.